Dirt cup with secondary cyclonic cleaning chambers

ABSTRACT

A vacuum cleaner includes a housing having a nozzle assembly and a canister assembly. A suction inlet is carried on the nozzle assembly. A dirt cup receiver is carried on the canister assembly. A suction generator is carried on the housing. The vacuum cleaner also includes a dirt cup assembly including (1) a dirt collection chamber having a first cylindrical sidewall and a tangentially directed inlet, (2) a first axially directed outlet, (3) a primary filter covering that outlet, (4) an air spreader, (5) a first feed passageway extending between the outlet and the spreader and (6) a secondary fine particle filter including multiple vortex chambers.

This application claims the benefit of U.S. Provisional Patent application Ser. No. 61/025,932 filed on 4 Feb. 2008.

TECHNICAL FIELD

The present invention relates generally to the floor care appliance field and, more particularly, to a vacuum cleaner incorporating a dirt cup including a series of secondary cyclonic cleaning chambers.

BACKGROUND OF THE INVENTION

A vacuum cleaner is an electro-mechanical appliance utilized to effect the dry removal of dust, dirt and other small debris from carpets, rugs, fabrics or other surfaces in domestic, commercial and industrial environments. In order to achieve the desired dirt and dust removal, most vacuum cleaners incorporate a rotary agitator. The rotary agitator is provided to beat dirt and debris from the nap of the carpet or rug while a pressure drop or vacuum is used to force air entrained with this dirt and debris into the nozzle of the vacuum cleaner. The particulate laden air is then drawn into a dirt collection vessel. The air is then drawn through a filter before being directed through the motor of the suction generator to provide cooling. Finally, the air is filtered to remove any fine particles of carbon from the brushes of that motor or other dirt that might remain in the airstream before being exhausted back into the environment.

Often the dirt collection vessel is designed to produce cyclonic airflow by providing that vessel with a dirt chamber having a cylindrical sidewall and a tangentially directed air inlet. This arrangement forces the air to swirl around the dirt collection chamber in the manner of a cyclone. The centrifugal force that is produced causes dirt and debris to move toward and against the cylindrical sidewall of the chamber while relatively clean air may be drawn off from the center of the chamber through a filter toward the suction generator.

Under most operating conditions most or all of the dirt and debris is removed from the airstream by the cyclonic airflow. At times, however, some dirt and debris remains entrapped within the airstream. Typically, that dirt and debris is relatively fine dirt particles of light weight which are not as susceptible to the centrifugal separation force produced by the cyclonic airflow. Over time such fine particles may become entrapped and fill the pores of the filter media thereby restricting airflow and reducing the cleaning efficiency of the vacuum cleaner. Eventually the cleaning efficiency of the vacuum cleaner becomes so impaired it is necessary for the operator to either clean or change the filter in order to achieve the desired level of cleaning.

The present invention relates to a vacuum cleaner having a dirt cup equipped with multiple secondary cyclonic cleaning chambers. These chambers function to efficiently and effectively remove fine dust particles remaining in the air stream. Advantageously, air flow is directed through the dirt cup in a manner to enhance cleaning power and efficiency.

SUMMARY OF THE INVENTION

In accordance with the purposes of the present invention as described herein, a novel vacuum cleaner is provided. That vacuum cleaner includes a housing having a nozzle assembly and a canister assembly. A suction inlet is carried on the nozzle assembly. A dirt cup receiver is carried on the canister assembly. A suction generator is carried on the housing. In addition, the vacuum cleaner includes a dirt cup assembly.

The dirt cup assembly includes a dirt collection chamber having a first cylindrical sidewall, a first tangentially directed inlet, a first axially directed outlet, a primary filter covering the axially directed outlet, an air spreader, a first feed passageway extending between the outlet and the air spreader and a secondary fine particle filter.

The secondary fine particle filter includes multiple vortex chambers. The multiple vortex chambers are downstream from and fed by the air spreader. Each of the vortex chambers includes a second cylindrical sidewall, a second tangentially directed inlet, a second axially directed outlet, a fine particle outlet, a second feed passageway, a fine particle trap provided in the dirt collection chamber and a discharge outlet. The discharge outlet is connected to each second axially directed outlet of the secondary fine particle filter. The discharge outlet leads to the suction generator.

In the following description there is shown and described several different embodiments of the invention, simply by way of illustration of some of the modes best suited to carry out the invention. As it will be realized, the invention is capable of other different embodiments and its several details are capable of modification in various, obvious aspects all without departing from the invention. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated herein and forming a part of the specification, illustrate several aspects of the present invention and together with the description serve to explain certain principles of the invention. In the drawings:

FIG. 1 is a perspective view of an upright vacuum cleaner constructed in accordance with the teachings of the present invention;

FIG. 2 is a detailed cross sectional view of the dirt cup assembly provided in the vacuum cleaner of the present invention;

FIG. 3 is a cross-sectional view through line 33 of FIG. 2; and

FIG. 4 is a perspective view of the dirt cup assembly insert, including the main body, the primary filter, cylindrical wall element of the fine particle trap and air guides, connected to the door that closes the bottom of the dirt collection chamber.

Reference will now be made in detail to the present preferred embodiments of this invention, an example of which is illustrated in the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

Reference is now made to FIG. 1 showing the upright vacuum cleaner 10 of the present invention. The upright vacuum cleaner 10 includes a housing comprising a nozzle assembly 14 and a canister or handle assembly 16. The handle assembly 16 includes a control handle 18 and a handgrip 20. A control switch 22 is provided for turning the vacuum cleaner 10 on and off. Of course, electrical power is supplied to the vacuum cleaner 10 from a standard electrical wall outlet through an electrical cord (not shown). Alternatively, the vacuum cleaner 10 could be powered by battery if desired.

A pair of rear wheels 24 (only one illustrated) are provided on the lower portion of the handle assembly 16 and a pair of front wheels (not shown) are provided on the nozzle assembly 14. Together, these wheels support the vacuum cleaner 10 for movement across the floor. To allow for convenient storage of the vacuum cleaner 10, a foot latch 26 functions to lock the canister assembly in an upright position as shown in FIG. 1. When the foot latch 26 is released, the handle assembly 16 may be pivoted relative to the nozzle assembly 14 as the vacuum cleaner 10 is manipulated back and forth to clean the floor.

In the presently illustrated embodiment, the handle assembly 16 includes a dirt cup receiver 28 in the form of a cavity adapted to receive and hold the dirt cup assembly 32. As illustrated in FIG. 2, the dirt cup assembly 32 may take the form of a dirt cup and lid 34 including a dirt collection chamber 30 having a cylindrical sidewall 36, a tangentially directed inlet 38 (partially obscured in FIG. 2) and an axially directed outlet 40. Typically, the dirt collection chamber 30 has a total volume of between about 800 and about 1600 cc. A primary filter 42 is provided in the dirt cup 34 over the axially directed outlet 40. The primary filter 42 is cylindrical in shape and concentrically received within the cylindrical sidewall 36 of the dirt cup 34. Such a structural arrangement induces cyclonic airflow in the dirt cup 34 and provides for enhanced cleaning efficiency. As will be described in greater detail below, the dirt cup assembly 32 also includes a secondary fine particle filter generally designated to reference number 50. The secondary fine particle filter 50 generally removes substantially any fine particles remaining in the air stream after it passes through the primary filter 42.

The nozzle assembly 14 includes a suction inlet 44. A rotary agitator 46 is carried on the nozzle assembly 14 so as to extend across the suction inlet 44. A suction generator 48, including a fan and a cooperating drive motor, is carried on the handle assembly 16. The suction generator 48 functions to generate a vacuum air stream for drawing dirt and debris from the surface to be cleaned. The rotary agitator 46 is connected by power take off to the motor of the suction generator 48. While the suction generator 48 is illustrated as being carried on the handle assembly 16, it should be appreciated that, alternatively, it could be carried on the nozzle assembly 14 if desired.

During normal vacuum cleaner operation, the rotary agitator 46 is driven by the motor of the suction generator 48 and functions to beat dirt and debris from the nap of an underlying carpet. The suction generator 48 functions to draw a vacuum air stream into the suction inlet 44. Dirt and debris from the carpet is entrained in the air stream, which is then drawn by the suction generator 48 into the dirt cup 34. Dirt and debris is captured in the dirt collection chamber 30 of the dirt cup 34 while relatively clean air is drawn through the primary filter 42. That air stream then passes through the secondary fine particle filter 50 before passing over the motor of the suction generator 48 to provide cooling. The air is then exhausted through a final filter (not shown), such as a HEPA filter, before being exhausted through an exhaust port 52 into the environment.

Reference is now made to FIGS. 2-4 that more clearly illustrate the dirt cup assembly 32 and, more particularly, the secondary fine particle filter 50 of the dirt cup assembly. As best illustrated in FIG. 2, the dirt cup assembly 32 includes a primary insert 54 concentrically received within the side wall 36 of the dirt cup 34. A first feed passageway 56 is defined between the main body 75 of the primary insert 54 and the sidewall 36. The first feed passageway 56 extends from the axial outlet 40 of the dirt collection chamber to an air spreader 58. Air spreader 58 includes an upstream end 59 having a diameter D₁ and a downstream end 61 having a diameter D₂ where D₁<D₂. Further, the air spreader 58 includes a wall 63 that diverges from the upstream end 59 to the downstream end 61. This sidewall 63 provides a smooth, continuously expanding flow surface that spreads the air stream to feed multiple vortex chambers 60 of the secondary fine particle filter 50. As illustrated, five vortex chambers 60 are provided. It should be appreciated, however, the invention embodies a secondary fine particle filter 50 incorporating anywhere from two to perhaps as many as twenty vortex chambers 60. Typically, the vortex chambers 60 have a total volume of between about 400 and about 500 cc.

Each vortex chamber 60 includes a second cylindrical sidewall 64, a second tangentially directed inlet 66 and a second axially directed outlet 68. Further, each vortex chamber 60 includes a fine particle outlet 70 at the bottom thereof that opens to a second feed passageway 72. The second feed passageway 72 extends between each of the fine particle outlets 70 of the vortex chambers 60 and a fine particle trap 74 provided in the dirt collection chamber 30. More specifically, the fine particle trap 74 is defined by a cylindrical wall element 76 that is concentrically received within the sidewall 36. The wall element 76 has a first open end connected to and in communication with the main body 75 of the primary insert 54 and a second open end connected in a cylindrical slot 78 carried on the door 80 of the dirt cup assembly 32. As should be appreciated, the door 80 is connected by a hinge 82 to the sidewall 36 of the dirt cup 34. The door 80 may be opened in a manner described in detail below to empty dirt and debris from the dirt cup assembly 32. Typically, the fine particle trap 74 has a total volume of between about 500 and about 800 cc.

As best illustrated in FIGS. 2 and 3, an air guide 84 is provided at the bottom of each vortex chamber 60. More specifically, the air guide 84 projects upwardly towards the second axially directed outlet 68. As illustrated, the air guide 84 may be substantially conical in shape. Further, the air guide 84 is concentrically received within the cylindrical sidewall 64 of the vortex chamber 60. In addition, the fine particle outlet 70 is provided at the bottom of the chamber 60 between the air guide 84 and the second cylindrical side wall 64. The air guide 84 functions to smooth the cyclonic air flow in the vortex chamber 60 in order to provide better separation of fine particles from the air stream that is exhausted from each vortex chamber.

During vacuum cleaner operation, dirt and debris is delivered from the suction inlet 44 through the tangentially directed inlet 38 into the annular shaped dirt collection chamber 30. That air stream rapidly flows around the annular dirt collection chamber 30 (note action arrows A). As a result of this cyclonic action, the dirt and debris moves under the influence of centrifugal force toward the cylindrical sidewall 36. The dirt and debris then moves under the force of gravity toward the bottom wall or door 80 of the dirt collection chamber 30. Simultaneously, the clean air is drawn through the apertures in the primary filter 42 and along the first feed passageway 56 to the air spreader 58 (note action arrows B and C). The air spreader 58 functions to direct substantially equal quantities of air to each of the vortex chambers 60. Air is delivered into each vortex chamber 60 through the tangentially directed inlets 66. Upon entering the vortex chamber 60, the air flows around the vortex chamber 60 in cyclonic fashion. Any remaining fine particles of dirt and debris are influenced by the centrifugal force generated by the cyclonic air flow and are moved toward the cylindrical side wall 64. These particles are then drawn by the force of gravity downwardly toward the bottom wall 62 of the vortex chamber 60 where they pass through the fine particle outlet 70 and the second feed passageway 72 to the fine particle trap 74. The clean air, now substantially void of fine particles, is then drawn through the axial outlet 68 into the outlet manifold 86 and then through the discharge outlet 88 leading to the suction generator 48. Advantageously, the cylindrical air guide 84 is concentrically received at the bottom of the chamber 60 within the sidewall 64. The high point or peak 90 of each air guide 84 is aligned with the axially outlet 68. The air guide 84 functions to eliminate turbulence in the vortex chamber 60 and smooth the air flow so as to allow better separation of clean air and fine particles.

After vacuum cleaner operation, the user may desire to empty dirt and debris from the dirt cup assembly 32. First the operator turns off the suction generator 48 of the vacuum cleaner 1 0. Next the operator releases a latch (not shown) in order to release the dirt cup assembly 32 from the dirt cup receiver 28 of the canister assembly 16. The operator then holds the dirt cup assembly 32 over a trash can or garbage bag. Next, the operator releases the resilient latch 92 carried on the door 80 from the latch pin 94 carried or formed on the sidewall 36. When this is done the door 80 swings open on the hinge 82. As a consequence, the bottom of the dirt cup assembly 32 opens and dirt and debris falls into the garbage can or trash bag from the dirt collection chamber 30 and the fine particle trap 74. After emptying the dirt cup assembly 32, the operator swings the door 80 on the hinge 82 closed ensuring that the latch 92 again fully engages the latch pin 94 to secure the door in position. The dirt cup assembly 32 is then reinserted in the receiver 28 on the canister assembly and the vacuum cleaner is again ready for operation.

The foregoing description of the preferred embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled. The drawings and preferred embodiments do not and are not intended to limit the ordinary meaning of the claims in their fair and broad interpretation in any way. 

1. A vacuum cleaner comprising: a housing including a nozzle assembly and a canister assembly; a suction inlet carried on said nozzle assembly; a dirt cup receiver carried on said canister assembly; a suction generator carried on said housing; and a dirt cup assembly including a dirt collection chamber having a first cylindrical sidewall, a first tangentially directed inlet, a first axially directed outlet, a primary filter covering said axially directed outlet, an air spreader, a first feed passageway extending between said outlet and said air spreader, a secondary fine particle filter including multiple vortex chambers downstream from and fed by said air spreader, each said vortex chamber including a second cylindrical sidewall, a second tangentially directed inlet and a second axially directed outlet, a fine particle outlet, a second feed passageway, a fine particle trap provided in said dirt collection chamber and a discharge outlet connected to each said second axially directed outlet of said secondary fine particle filter, said discharge outlet leading to said suction generator.
 2. The vacuum cleaner of claim 1 further including an air guide at a bottom of each of said multiple vortex chambers and projecting upwardly toward said second axially directed outlet.
 3. The vacuum cleaner of claim 2, wherein said air guide is substantially conical in shape.
 4. The vacuum cleaner of claim 3, wherein said air guide is concentrically received within said second cylindrical sidewall of said vortex chamber and said fine particle outlet is provided between said air guide and said second cylindrical sidewall.
 5. The vacuum cleaner of claim 4, wherein said fine particle trap comprises a cylindrical element concentrically received in said first sidewall of said dirt collection chamber.
 6. The vacuum cleaner of claim 1, wherein said multiple vortex chambers of said secondary fine particle filter have a total volume of between about 400 cc and about 500 cc.
 7. The vacuum cleaner of claim 6, wherein said dirt collection chamber has a total volume of between about 800 cc and about 1600 cc.
 8. The vacuum cleaner of claim 7, wherein said fine particle trap has a total volume of between about 500 cc and about 800 cc.
 9. The vacuum cleaner of claim 8, wherein said secondary fine particle filter includes five vortex chambers.
 10. The vacuum cleaner of claim 1, wherein said collection chamber includes an access door that is opened to empty dirt from said dirt collection chamber and said fine particle trap.
 11. The vacuum cleaner of claim 10, wherein said door forms a bottom wall of said dirt collection chamber.
 12. The vacuum cleaner of claim 11, wherein said door is connected to said first sidewall by a hinge.
 13. The vacuum cleaner of claim 1, wherein said canister assembly is pivotally connected to said nozzle assembly.
 14. The vacuum cleaner of claim 13, further including a rotary agitator carried on said nozzle assembly adjacent said suction inlet.
 15. The vacuum cleaner of claim 1, wherein said air spreader includes an upstream end having a first diameter D₁ and a downstream end having a second diameter D₂ where D₁<D₂.
 16. The vacuum cleaner of claim 15, wherein said spreader includes a sidewall diverging from said upstream end toward said downstream end. 